CHAPTER TOOLS

Keywords:

hydroxyapatite;

atmospherically plasma sprayed;

crystalline phases;

fourier transform infrared (FTIR);

oxyhydroxyapatite

Summary

Plasma sprayed hydroxyapatite (HA) coatings have been widely used for dental and orthopedic applications for fast fixation between the implant and the human anatomy. In this study, the HA coatings were atmospherically plasma sprayed (APS) using different spray power and stand-off distance (SOD), and the coating surfaces were characterized using various methods. X-ray diffraction (XRD) revealed the presence of crystalline HA, amorphous calcium phosphate (ACP) and some other crystalline phases including tricalcium phosphate (α-TCP and β-TCP), tetracalcium phosphate (TTCP) and calcium oxide (CaO). Fourier transform infrared (FIIR) spectroscopy showed that both OH− and PO43- bands of HA changed after spraying and the HA phase identified by XRD was actually the solid solution of oxyapatite (OAp) in HA, i.e., oxyhydroxyapatite (OHA). The phase composition of the HA coatings varied with respect to the spray power and SOD. The surface morphology and roughness were analyzed via scanning electron microscopy (SEM) and profilometry respectively, and the results related to the phase composition.